The present invention relates to battery retaining mechanisms for use with forklift trucks and, more particularly, to such a device which is easily releasable.
Forklift trucks are typically used to transport and handle goods and containers which are relatively large or heavy. Forklift trucks may be powered by an electric D.C. motor connected to rechargeable storage batteries which are carried on the truck. The batteries are typically 12, 24, 36, 48 or 72 volts. Some forklift truck models weigh more than 8,000 pounds, with the batteries alone weighing several hundred pounds.
A pair of lift forks are mounted on an extendable fork mast for engaging the goods or containers being handled. The forks are raised as the goods or containers are carried by the truck. Additionally, the forks may be raised quite high, depending upon the construction of the truck, in order to position the goods or containers on a storage rack or to remove the goods or containers from such a rack.
Normally, a battery is rolled into the battery compartment until it rests against the rear wall of the battery compartment. A battery retainer, designed to keep the battery in the battery compartment can be secured to the side wall of the truck, however, typically a gap exists between the battery and battery retainer, to allow for battery length variations thus permitting the battery to roll back and forth while the truck is in an operative mode. The length of the tolerance of the batteries is typically 3/32", such that two batteries could differ up to 3/16" in length.
This variation in battery length permits the battery to effectively crash into the battery retaining plate, which plate is held on to the forklift by an upwardly projecting section of sheet metal which is part of the structural housing of the power unit. The banging of the shifting batteries also irritates the forklift driver. Furthermore, in forklift trucks having rear steer wheels and guidance systems, lateral shifting of the batteries might adversely affect the accuracy of the steering especially when the vehicle is in the automatic guidance mode.
Attempts have been made to remedy the above situation by furnishing a spacer means which is typically formed from a planar spacer plate located parallel to the side wall of the truck. The plate is secured to a U-shaped plate, the legs of which are welded to the retainer plate. The planar bottom portion of the U-shaped plate is also located parallel to the side wall of the truck. The spacer plate is secured to the U-shaped plate by countersunk fastening means, which extend into the space between the U-shaped plate and the battery retainer plate.
Unfortunately, the use of such spacers presents practical limitations. For example, if the battery presses so hard against the spacer that the spacer becomes wedged against the U-shaped plate, removal of the plate for purposes of changing the battery is made extremely difficult. This problem is compounded by the fact that these batteries must be recharged at the end of each eight or twelve hour shift. The inconvenience associated with freeing the battery retainer plate can constitute an unnecessary, or at least an unwelcome, expenditure of time, money and energy.
Still another problem related to existing spacer means is the fact that since the batteries can vary slightly in overall length, the distance between the battery retaining plate and the spacer may have to be adjusted as often as every battery change. This adjustment typically is made by means of the screw threaded fastening means members which must be turned one at a time by hand, thereby incurring additional expenditures of time, money and energy. Sometimes the adjustment requires adding an additional spacer between the battery and the existing spacer.
It is thus apparent that the need exists for an improved battery retainer or the like which provides for quick and easy removal of the battery retaining plate while at the same time precluding the side-to-side shifting of the battery in the forklift.